Sierra Metals announces modification on share repurchase plan after graduation to the TSX

VANCOUVER, Aug. 23, 2013 /PRNewswire/ - Sierra Metals Inc. (TSX:SMT) (BVL:SMT) ("Sierra Metals" or the "Company") announces that it
has signed an amended and restated dealer agreement (the "AmendedAgreement") with a designated broker(the "Broker") in respect of its previously announced normal course issuer bid ("NCIB"). The Company and the Broker entered into a dealer agreement dated
March 26, 2013, as amended on May 10, 2013, whereby the Broker was
engaged to operate an automatic share purchase plan (the "ASPP") under the NCIB. Reference should be made to the Company's press
releases dated March 26, 2013 and May 10, 2013, respectively, for
further details regarding the ASPP and the NCIB.

The primary amendment agreed between the parties under the Amended
Agreement is the conversion of the ASPP into a discretionary share
purchase plan (the "DSPP"). Pursuant to the DSPP, the Broker will only trade with the Company's
expressed instructions. The NCIB will end on April 1, 2014.

About Sierra Metals

Sierra Metals Inc. is a Canadian mining company focused on precious and
base metals from its Yauricocha Mine in Peru, its Bolivar Mine and Cusi
Mine in Mexico. In addition, Sierra Metals is exploring several
precious and base metal targets in Peru and Mexico. Projects in Peru
include Adrico (gold), Victoria (copper-silver) and Ipillo
(polymetallic) at the Yauricocha Property in the province of Yauyos and
the San Miguelito gold properties in Northern Peru. Projects in Mexico
include Bacerac (silver) in the state of Sonora, La Verde (gold) at the
Batopilas Property in the state of Chihuahua, and Las Coloradas
(silver) at the Melchor Ocampo Property in the state of Zacatecas.

The Company's shares trade on the Bolsa de Valores de Lima and the
Toronto Stock Exchange under the symbol "SMT".

Forward-Looking Statements

Except for statements of historical fact contained herein, the
information in this press release may constitute "forward-looking
information" within the meaning of Canadian securities law. Other than
statements of historical fact, all statements are "forward-looking
statements", which involve various known and unknown risk and
uncertainties and other factors, including market conditions that may
affect the Company's ability to execute its current business plan.
Actual results might differ materially from results suggested in any
forward-looking statements. The Company assumes no obligation to update
the forward-looking statements, or to update the reasons why actual
results could differ from those reflected in the forward-looking
statements unless and until required by securities laws applicable to
the Company. Additional information identifying risks and uncertainties
is contained in filings by the Company with the Canadian securities
regulators, which filings are available at www.sedar.com.